Heat exchange unit



June 23, i942. c. D. ROGERS HEM.` EXCHANGE UNIT Filed Aug. 21, 1940 2 Sheets-Sheet 1 Tru wm Hm INVENTOR ,5M T E www H UW E dJ F u E. EQU m ATTORNEYS 2 Sheets-Sheet 2 INVENTOR Efe .U Hugs-:Ins BY MM,

G. D. ROGERS HEAT EXCHANGE UNIT Filed Aug. 21, 1,940

June 23, 1942.

Patented June 23, 1942 HEAT EXCHANGE UNIT George D. Rogers, United States Army,

v Dover, N. J.

Application August 21. 1940, serial No. 353,521

(Granted under the act of March 3,- 1883, as

amended April 30, 1928; 370 O. G. 757) 6 Claims.

The invention described herein may be manufactured and used by or for the Government for governmental purposes, without the payment to me of any royalty thereon.

This invention relates to heat exchange units peculiarly adapted to expedite the radiation and conduction of heat from tubular elements subjected to relatively high temperatures,Y such for example, as the gun barrels of automatic weapons.

The primary object of the invention is to pro-- vide an efficient radiator that may satisfactorily be substituted for the water or other liquid cooling apparatus presently used in the art for cooling the barrels of guns, especially the barrels of heavy automatic guns. f

A. further object of the invention is to utilize the blast of the gun to force a draft of air or similar gas at atmospheric temperature into conductive relation with the barrel through a predetermined length thereof only so that the maximum cooling effect of the conducting air or other gas may be realized.

The specific nature of the invention as well as other objects and advantages thereof will clearly appear from a description of a preferred embodiment as shown in the accompanying drawings in which:

Fig. 1 is a view in fragmentary side elevation showing the heat exchange unit of this invention;

Fig. 2 is a longitudinal sectional view taken on the line 2-2 of Fig. 1;

Fig. 3 is a transverse sectional view taken on the line 3-3 of Fig. 2;

Fig. 4 is a transverse sectional view takenon the line 4--4 of Fig. 2; Fig. 5 is` an end elevational view of one of the radiator sections of the heatexchange unit showing one cooling tube in position;

Fig. 6 is a View in side elevation of the vradiator section shown in Fig. 5;

Fig. 7 is a perspective view of a typical radiator section of the heat exchange unit of this invention;

Fig. 8 is a longitudinal sectional view of a typicalA radiator section of the heat exchange unit of this invention showing its associated cooling tubes.

Fig. 9 is a diagrammatic exploded view of a portion of the heat exchange unit showing the relative positions of the several radiator sections thereof.

Referring now to the drawings by characters of reference there is shown in Fig. 1 a heat exchange unit generally designated by the character I0 conforming with the present invention.

The heat exchange unit I0 as herein disclosed comprises a plurality of substantially identical radiator sections Il and a flash hider I2 assembled in longitudinal juxtaposed relation, with the radiator sections `conductively disposed circum-l jacently of a gun barrel I3.

Each radiator section II may be machined from any suitable bar stock of goodvheat conducting quality to provide one or more continuous helical heat radiating fins I4 and an axial bore I5 tapered toward its muzzle end and adapted to receive a corresponding section of the gun barrel I3 in snugly fitting circumjacent heat conducting relation. As shown in the instant embodiment of the invention the radiator sections II are triple threaded to provide three continuous helical radiating fins I4, and while it is preferred to employ three such radiating ns it will be understood of course that only one such fin I4 or any other number thereof may be used if desired solong as they are of helical form. Moreover in lieu of machining the radiator sections from bar stock as above described they may be cast if preferred.

Also each of the radiator sections II are provided with a plurality of circumferentially equispaced passages I6 extending through the fins thereof parallel to the axis of the section to receive fluid conduits I1 in the manner hereinafter described. The terminal edges of the fins I4 of each radiator section are recessed as indicated at I8 to accommodate the curvature of the conduits I'I associated with that section and each iin is I formed of outwardly converging section in such manner as to provide a seat I9 between adjacent ns next to the bore I5 that will heat conductively receive a conduit I1 and also provide sufficient clearance for introducing the conduit in its seat I9 past the burrs formed in drilling or otherwise providing the passages I6.

As shown more particularly in Figs. 5, 6 and 9 each radiator section II has a tubular conduit I1 wound under tension upon each of the seats I9 formed between adjacent convolutions of the fins I4 with the outer endA portions of each of the conduits projecting in opposed axial prolongation of passages I6 in alignment with the recesses I8. The conduits I1 project from either end of the radiator sections Il a sufficient distance to terminate in the plane of the muzzle or breech of the heat exchange unit as the case' may be and in the present form of the invention the sections Il are of sufficient length to receive two convolutions of each of the conduits I1 wound thereon. The conduits llat either end of the sections Il are upwardly directed from the seats I9 into engagement with outer arcuate portions fof the recesses I8, which are of such radius as to `permit bending of the conduits into opposed axial prolongation of the passage I6 aligned with the outer arcuate portions of opposed recesses, without deformation of the cross sectional contour of the conduits.

The number of passages IS formed in each radiator section II is the product of the number of conduits I1 wound upon each section. il and the number of sections employed to constitute the heat exchange unit Iii. For example in the present embodiment where the radiator sections il are triple threaded and therefore have three conduits II wound upon each section and the heat exchange unit is comprised of eight radiator sections each section l! will have twentyfour passages i as indicated in Figs. 3 to 5 and 7.` It is not to be understood, however, that the embodiment shown islimitative in character for the sections il may be arranged to have any suitable number of conduits il wound thereupon one or more convolutions and the heat exchange unit may comprise any desired number of sections lI, but the number of passages It in each section I i as hereinafter made apparent must be the product of the number of sections li and number of conduits il convoluted upon each section il.

With the radiator sections il formed as de' scribed and the conduits il wound upon the seats I9 thereof as aforesaid, reference is made to Figs. 1, 2, 8 and 9 which clearly show the method of assembly ofthe sections in the assembled heat exchange unit. The upper leftmost section of Fig. 9 viewed in its normal position and hereinafter referred to as the muzzle radiator section is retained in the position shown in Fig. 9 and the next consecutive radiator section I i' is assembled in axial juxtaposed relation with the muzzel section il by projecting the muzzle end portions of the conduits Il wound thereupon through those passages i6 of the muzzle radiator section which will be aligned with the conduits II of the succeeding section when the beveled ends lil of the threads or fins i4 of the adjacent ends of the sections are in complementary abutting relation. Successive radiator sections li are assembled in juxtaposed relation with preceding radiator sections in the same manner as the muzzle radiator section II and its succeeding radiator section are assembled. The muzzle end portions of the conduits I'I of each succeeding radiator section i I project forwardly a suiiicient distance tobe inserted through cooperating aligned passages I6 of the preceding radiator sections and terminate in the plane of the projecting muzzle end portions of the conduits Il wound upon the muzzle radiator section il, likewise the breech end portions of the conduits i'I project through cooperating aligned passages l of succeeding radiator sections I I and terminate in a plane adjacent. the breech end of the breech radiator section Il. It will of course be obvious that the sections I I need not be assembled with their beveled end portions I4' in complementary abutting relation, however, this method is preferred inasmuch as the fins I4 will then be disposed to form a smooth helical surface from muzzle to breech.

At the breech end of the heat exchange unit thus far assembled the conduits il are all passed through a plate 29 conveniently of the same diameter as the outside diameter of the radiator sections I Iv and secured thereto by a rolling operation similar to that employed in securing boiler tubes to a boiler.

The flash hider I2 comprisesan outer member having a forward .portion 20 of generally cylindrical tubular form of greater diameter than a bore I5 of a radiator section Ii and a rearwardly projecting axially disposed portion 2| taper bored in such manner as to form the annular shoulder 22. adjacent its junction with the cylindrical portion 2B and a rear or apical opening 23 of the same vdiameter as. a bore i5. The portions 20 and 2i are provided with annular heat radiating fins 24 which are preferably gradated in outside diameter from rear to .front so as to form a continuation of the fins il over the entire heat exchange `unit which is smooth in longitudinal sectional contour as shown in Fig. 2.

The iins 24 of the conical projecting portion 2l and shoulder 22 are bored to provide a circumferential row of passages 25 adapted to form prover in secured engagement with the shoulder 22.

The flash hider I2 also comprises an inner truncated conical member 2t adapted to be received in the taper bore of the portion 2l of the outer member and be secured to the muzzle end of the barrel I3. The muzzle end of the inner member 26 is formed to provide an annular passage 2l between the interior of. portion 2li of the outer member and the exterior of the inner member 26 leading from` the exterior of the ash hider. to the exit ends of the conduits il secured to the flash hider.

In operation the barrel i3 may be of the stationary or recoiling type as in either case the muzzle blast in iiring will cause a reduction in pressure in the vicinity of passage 2l whereupon atmospheric pressure existing in the vicinity of the breech. ends of the conduits Il will force air through the conduits from breech to muzzle. Due to the novel construction of this heat exchange unit a single conduit in making only a few convolutions in direct heat conducting relation with the portions of the radiator sections II in direct bearing with the barrel will prevent the air passing through the conduits from being raised to a temperature Where it is incapable of absorbing heat from `the barrel and at the same time because of the close spacing of the convolutions of the different conduits I'I the barrel will be more effectively cooled owing to the relatively cool air passed through the convolutions by this method.

Also as the barrel is heated and expands lineally it will engage the taper bores I5 of the radiator sections in better heat conducting relation.

Having now described what is at present considered a preferred embodiment of the invention and -being provided With l said ns in heat conducting relation,

2. A heat exchange unit comprising a metallic radiator portion, said radiator portion being formed to provide a longitudinal passage adapted to receive means for heat exchange, said'radiator portion also being provided with a plurality of outwardly extending radiator ns, said ns each having a plurality of spaced openings disposed in longitudinally aligned relation, and a plurality of tubular conduits, each extending longitudinally' through certain of said openings and having a part of their intermediate portions disposed between certain adjacent pairs of said ns in heat conducting relation to the metal between said pairs of ns.

3. A heat exchange unit adapted for use in cooling a gun barrel comprising a metallic radiator portion, said radiator portion being formed to provide a longitudinal passage adapted to conductively receive a gun barrel, said radiator portion also being provided with an outwardly eX- tending helical radiating n comprised of a plurality of convolutions, Aeach of said convolutions having formed therein a plurality of helically spaced openings disposed in longitudinallyv aligned relation, and a plurality of tubular con-v duits each extending longitudinally through cer,

tain of said openings and having a part of their intermediateportions disposed between certain of adjacent convolutions of said helical radiat.

ing fin in heat conducting relation to the metal between the convolutions of said n.-

4. In a heat exchange unit, a radiator portion comprising a plurality of axially bored radiator sections disposed in axially aligned juxtaposed relation adapted to receive the barrel of i a gun in heat conducting relation, each of said radiator sections also being provided withhelical radiator ns, said radiator sections being so relatively juxtaposed that thefins thereof will provide continuous helical radiator* fins of` a plurality of convolutions relative to the lradiator portion,continuous helical conduit seats formed between the convolutions of the continuous helical radiator ns, each of said Yconvolutions being provided with aplurality of spaced openings disposed in longitudinally aligned relation to form passages extending from end to end of said radiator portion, a tubular conduit wound upon each conduit seat portion of each radiator section, opposed end portions of said conduits of each radiator section being aligned with certain of said openings in the ns of the section and disposed within and extending from end to end respectively of the radiator portion of the heat exchange unit through the passages in the other radiator sections. k

5. The structure of claim 4, including an arrangement wherein the forwardly projecting end portions of the conduits of each section succeeding-the forward radiator section are extended through the passages next adjacent tothe open# ing with which the reawardly extending of the preceding section are aligned.

6. The structure of claim 4 including a ash hider adapted to be secured to the muzzle of said gun barrel comprising spaced concentric inner e and outer members juxtaposed in axial prolongation of the forward radiator section and said conduits are extended from the forward radiator section through said outer member in communication with the space betweerrsaid members.

GEORGE D. ROGERS.

portions 

